The type of a light source used by a projection device is evolved from an ultra-high pressure mercury lamp (UHP lamp), a light emitting diode (LED) to a laser diode (LD) in the wake of the market requirements on the projection device for luminance, color saturation, service life, and non-toxic environmental protection, etc.
In the field of high-luminance projection, the luminance of a projection system with a single digital micromirror device (DMD) is more difficult to meet the demand. In addition, the expensive price of the digital micromirror device leads to poor overall competitiveness of the product.
The information disclosed in this “BACKGROUND OF THE INVENTION” section is only for enhancement understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Furthermore, the information disclosed in this “BACKGROUND OF THE INVENTION” section does not mean that one or more problems to be solved by one or more embodiments of the invention were acknowledged by a person of ordinary skill in the art.